﻿/*!
\file ec_md5.h

\author unkown
\editor jiangyong
\email  kipway@outlook.com
\update 2020.9.6

functions:
	encode_md5
	encodestr_md5

eclib3.0 Copyright (c) 2017-2020, kipway
source repository : https://github.com/kipway

Licensed under the Apache License, Version 2.0 (the "License");
You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0
*/

#pragma once

#include <memory.h>
namespace md5
{
#ifndef POINTER
	typedef unsigned char *POINTER;
#endif

#ifndef UINT2
	typedef unsigned short UINT2;
#endif

#ifndef UINT4
	typedef unsigned int UINT4;
#endif

	typedef struct t_ma5_ctx {
		UINT4 state[4];
		UINT4 count[2];
		unsigned char buffer[64];
	} MD5_CTX;

#define S11 7
#define S12 12
#define S13 17
#define S14 22
#define S21 5
#define S22 9
#define S23 14
#define S24 20
#define S31 4
#define S32 11
#define S33 16
#define S34 23
#define S41 6
#define S42 10
#define S43 15
#define S44 21

	static const unsigned char PADDING[64] = {
		0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
	};

#define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
#define G(x, y, z) (((x) & (z)) | ((y) & (~z)))
#define H(x, y, z) ((x) ^ (y) ^ (z))
#define I(x, y, z) ((y) ^ ((x) | (~z)))
#define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
#define FF(a, b, c, d, x, s, ac) { \
		(a) += F ((b), (c), (d)) + (x) + (UINT4)(ac); \
		(a) = ROTATE_LEFT ((a), (s)); \
		(a) += (b);  \
		}

#define GG(a, b, c, d, x, s, ac) { \
		(a) += G ((b), (c), (d)) + (x) + (UINT4)(ac); \
		(a) = ROTATE_LEFT ((a), (s)); \
		(a) += (b); \
		}

#define HH(a, b, c, d, x, s, ac) { \
		(a) += H ((b), (c), (d)) + (x) + (UINT4)(ac); \
		(a) = ROTATE_LEFT ((a), (s)); \
		(a) += (b); \
		}

#define II(a, b, c, d, x, s, ac) { \
		(a) += I ((b), (c), (d)) + (x) + (UINT4)(ac); \
		(a) = ROTATE_LEFT ((a), (s)); \
		(a) += (b); \
		}

	class cMd5
	{
	public:
		static void Md5_Encode(const void *inBuf, unsigned int nsize, unsigned char outBuf[16])
		{
			MD5_CTX md5c;
			MD5Init(&md5c);
			MD5Update(&md5c, (const unsigned char *)inBuf, nsize);
			MD5Final(outBuf, &md5c);
		}

		static void MD5Init(MD5_CTX *context)
		{
			context->count[0] = context->count[1] = 0;
			context->state[0] = 0x67452301;
			context->state[1] = 0xefcdab89;
			context->state[2] = 0x98badcfe;
			context->state[3] = 0x10325476;
		}
		static void MD5Update(MD5_CTX *context, const unsigned char *input, unsigned int inputLen)
		{
			unsigned int i, index, partLen;

			index = (unsigned int)((context->count[0] >> 3) & 0x3F);

			if ((context->count[0] += ((UINT4)inputLen << 3)) < ((UINT4)inputLen << 3))
				context->count[1]++;
			context->count[1] += ((UINT4)inputLen >> 29);

			partLen = 64 - index;

			if (inputLen >= partLen) {
				memcpy((POINTER)&context->buffer[index], (POINTER)input, partLen);
				MD5Transform(context->state, context->buffer);

				for (i = partLen; i + 63 < inputLen; i += 64)
					MD5Transform(context->state, &input[i]);

				index = 0;
			}
			else
				i = 0;

			memcpy((POINTER)&context->buffer[index], (POINTER)&input[i], inputLen - i);
		}

		static void MD5Final(unsigned char digest[16], MD5_CTX *context)
		{
			unsigned char bits[8];
			unsigned int index, padLen;

			Encode(bits, context->count, 8);

			index = (unsigned int)((context->count[0] >> 3) & 0x3f);
			padLen = (index < 56) ? (56 - index) : (120 - index);
			MD5Update(context, PADDING, padLen);
			MD5Update(context, bits, 8);

			Encode(digest, context->state, 16);
			memset((POINTER)context, 0, sizeof(*context));
		}

		static void MD5Transform(UINT4 state[4], const unsigned char block[64])
		{
			UINT4 a = state[0], b = state[1], c = state[2], d = state[3], x[16];
			Decode(x, block, 64);

			FF(a, b, c, d, x[0], S11, 0xd76aa478);
			FF(d, a, b, c, x[1], S12, 0xe8c7b756);
			FF(c, d, a, b, x[2], S13, 0x242070db);
			FF(b, c, d, a, x[3], S14, 0xc1bdceee);
			FF(a, b, c, d, x[4], S11, 0xf57c0faf);
			FF(d, a, b, c, x[5], S12, 0x4787c62a);
			FF(c, d, a, b, x[6], S13, 0xa8304613);
			FF(b, c, d, a, x[7], S14, 0xfd469501);
			FF(a, b, c, d, x[8], S11, 0x698098d8);
			FF(d, a, b, c, x[9], S12, 0x8b44f7af);
			FF(c, d, a, b, x[10], S13, 0xffff5bb1);
			FF(b, c, d, a, x[11], S14, 0x895cd7be);
			FF(a, b, c, d, x[12], S11, 0x6b901122);
			FF(d, a, b, c, x[13], S12, 0xfd987193);
			FF(c, d, a, b, x[14], S13, 0xa679438e);
			FF(b, c, d, a, x[15], S14, 0x49b40821);


			GG(a, b, c, d, x[1], S21, 0xf61e2562);
			GG(d, a, b, c, x[6], S22, 0xc040b340);
			GG(c, d, a, b, x[11], S23, 0x265e5a51);
			GG(b, c, d, a, x[0], S24, 0xe9b6c7aa);
			GG(a, b, c, d, x[5], S21, 0xd62f105d);
			GG(d, a, b, c, x[10], S22, 0x2441453);
			GG(c, d, a, b, x[15], S23, 0xd8a1e681);
			GG(b, c, d, a, x[4], S24, 0xe7d3fbc8);
			GG(a, b, c, d, x[9], S21, 0x21e1cde6);
			GG(d, a, b, c, x[14], S22, 0xc33707d6);
			GG(c, d, a, b, x[3], S23, 0xf4d50d87);
			GG(b, c, d, a, x[8], S24, 0x455a14ed);
			GG(a, b, c, d, x[13], S21, 0xa9e3e905);
			GG(d, a, b, c, x[2], S22, 0xfcefa3f8);
			GG(c, d, a, b, x[7], S23, 0x676f02d9);
			GG(b, c, d, a, x[12], S24, 0x8d2a4c8a);


			HH(a, b, c, d, x[5], S31, 0xfffa3942);
			HH(d, a, b, c, x[8], S32, 0x8771f681);
			HH(c, d, a, b, x[11], S33, 0x6d9d6122);
			HH(b, c, d, a, x[14], S34, 0xfde5380c);
			HH(a, b, c, d, x[1], S31, 0xa4beea44);
			HH(d, a, b, c, x[4], S32, 0x4bdecfa9);
			HH(c, d, a, b, x[7], S33, 0xf6bb4b60);
			HH(b, c, d, a, x[10], S34, 0xbebfbc70);
			HH(a, b, c, d, x[13], S31, 0x289b7ec6);
			HH(d, a, b, c, x[0], S32, 0xeaa127fa);
			HH(c, d, a, b, x[3], S33, 0xd4ef3085);
			HH(b, c, d, a, x[6], S34, 0x4881d05);
			HH(a, b, c, d, x[9], S31, 0xd9d4d039);
			HH(d, a, b, c, x[12], S32, 0xe6db99e5);
			HH(c, d, a, b, x[15], S33, 0x1fa27cf8);
			HH(b, c, d, a, x[2], S34, 0xc4ac5665);


			II(a, b, c, d, x[0], S41, 0xf4292244);
			II(d, a, b, c, x[7], S42, 0x432aff97);
			II(c, d, a, b, x[14], S43, 0xab9423a7);
			II(b, c, d, a, x[5], S44, 0xfc93a039);
			II(a, b, c, d, x[12], S41, 0x655b59c3);
			II(d, a, b, c, x[3], S42, 0x8f0ccc92);
			II(c, d, a, b, x[10], S43, 0xffeff47d);
			II(b, c, d, a, x[1], S44, 0x85845dd1);
			II(a, b, c, d, x[8], S41, 0x6fa87e4f);
			II(d, a, b, c, x[15], S42, 0xfe2ce6e0);
			II(c, d, a, b, x[6], S43, 0xa3014314);
			II(b, c, d, a, x[13], S44, 0x4e0811a1);
			II(a, b, c, d, x[4], S41, 0xf7537e82);
			II(d, a, b, c, x[11], S42, 0xbd3af235);
			II(c, d, a, b, x[2], S43, 0x2ad7d2bb);
			II(b, c, d, a, x[9], S44, 0xeb86d391);

			state[0] += a;
			state[1] += b;
			state[2] += c;
			state[3] += d;

			memset((POINTER)x, 0, sizeof(x));
		}
		static void Decode(UINT4 *output, const unsigned char *input, unsigned int len)
		{
			unsigned int i, j;

			for (i = 0, j = 0; j < len; i++, j += 4)
				output[i] = ((UINT4)input[j]) | (((UINT4)input[j + 1]) << 8) |
				            (((UINT4)input[j + 2]) << 16) | (((UINT4)input[j + 3]) << 24);
		}
		static void Encode(unsigned char *output, UINT4 *input, unsigned int len)
		{
			unsigned int i, j;

			for (i = 0, j = 0; j < len; i++, j += 4) {
				output[j] = (unsigned char)(input[i] & 0xff);
				output[j + 1] = (unsigned char)((input[i] >> 8) & 0xff);
				output[j + 2] = (unsigned char)((input[i] >> 16) & 0xff);
				output[j + 3] = (unsigned char)((input[i] >> 24) & 0xff);
			}
		}
	};
}// namespace md5

namespace ec
{
	inline void encode_md5(const void *inBuf, unsigned int nsize, unsigned char outBuf[16])
	{
		if(inBuf && nsize)
			md5::cMd5::Md5_Encode(inBuf, nsize, outBuf);
	}
	inline void encodestr_md5(const char *inBuf, unsigned char outBuf[16])
	{
		if(inBuf)
			md5::cMd5::Md5_Encode(inBuf, (unsigned int)strlen(inBuf), outBuf);
	}
}


